First ever chargeback

Hi all,

 

Today i received my first ever paypal chargeback for an item i posted in December. The strange thing is, the buyer left postive feedback after they recieved it. Would they be trying to scam me?

 

It was sent as a registered post letter so i have proof of where it went to on the Australia Post lodgement receipt and the tracking shows as delivered.  So i'm just wondering if there's a chance i'll win the dispute with the delivery proof and the buyer leaving feedback?